Equipment Operation A: Gas Analyzers Flashcards
What’s the carrier gas in gas chromatography?
Helium
If you’re using gas chromatography to detect helium, then what do you use as the carrier gas?
Use Neon
If you’re troubleshooting your gas chromatography machine, you should look for ___ and ___ because they will disrupt gas chromatography.
Water and CO2
How does gas chromatography work? Gases pass through a ___ where differing sizes of molecules for the individual gases make each gas exit at different rates.
Separator column
What gasses are measured with gas chromatograph?
Ne, O2, N2, CO.
What are the advantages of gas chromatography? (x3)
Very accurate and can analyze many gases at once.
Also you only need a small amount of gas.
What are the disadvantages of gas chromatography? (x1)
Takes a long time to do.
In mass spectrometry, a sample gas is drawn by ___ into an ___. The individual gases are ___ and analyzed to measure ___.
Vacuum
Ionization chamber
Seperated
Gas percentage
What are the advantages of mass spectrometry?
Fast. Can be done breath to breath. Can measure multiple gases at the same time.
What are the disadvantages of mass spectrometry?
Very expensive, large in size, and requires a lot of maintenance.
What gases are measured in mass spectrometry?
Helium, N2, O2, CO2.
What gas is N2?
Nitrogen
On the test, they give you a bunch of gases and percentages. First thing you want to do is __.
Add them up.
If they don’t add up to 100%, there’s an error.
If they add up to almost 100%, then adjust the gain.
If they add up to over 100%, then reduce the gain.
What does an infrared absorption analyzer measure?
Carbon dioxide, carbon monoxide, and methane.
A chopper motor and a chopper blade are parts of a ___.
Infrared Absorption Analyzer
How do you calibrate an infrared absorption analyzer?
First calibrate low end. Use room air.
Then calibrate high end, use 0.3% of carbon monoxide or carbon dioxide.
Then do low end calibration again.
What happens if you have a long sampleing line on any type of analyzer?
Readings will be delayed.
What does a thermal conductivity analyzer detect?
It’s also known as ___.
Helium
Wheatstone Bridge Analyzer.
Keep thermal conductivity analyzers away from ___ gases.
Combustable gases. (Helium doesn’t burn.)
Thermal conductivity analyzers should be calibrated to ___.
Then calibrate with ___.
Then re-zero with ___.
Room air
10% helium
Room air.
What does a Geissler Tube Ionizer detect?
Nitrogen (N2)
To calibrate a geissler tube ionizer, use __.
Then use ___
Then use ___ to re-zero it.
100% O2 (Can’t use room air because it has N2 in it.)
Then use a different amount of O2 for the high end (amount varies)
Then 100% O2 to re-zero.
If there’s erratic readings, or “spikes” on the Geissler Tube Ionizer, what’s that caused by?
Moisture
If the Geissler Tube Ionizer isn’t working, it might be a problem with the ___ or the ___.
Pump or the seals might not be tight.
How does a gas analyzer work? It has a ____. It’s specialized dirt. What it does is the gas passes through the dirt and each gas passes through at its own speed. Since we know what gas comes out first second third and fourth, we can know what gasses they are. You need a ___.
It has a separator column.
You need a carrier gas.
What is another name for gas chromatography analyzer?
Absorption type analyzer.
What is another name for an absorption type analyzer?
Gas chromatography.
List two things that will mess up gas analyzers and should be checked for when troubleshooting.
Long sampling lines and moisture
